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Significant Accounting Policies - Additional Information (Detail)	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2012	Sep. 30, 2016 USD ($) shares	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Segment shares	Sep. 30, 2015 USD ($) shares	Dec. 31, 2015 USD ($) shares	Nov. 30, 2015 USD ($)	Jun. 30, 2015 Tranche	Mar. 05, 2015 USD ($)	Dec. 31, 2014 shares	May 31, 2014 USD ($)	Dec. 31, 2012 USD ($)	Dec. 06, 2012 USD ($)
Significant Accounting Policies [Line Items]
Sales discount percentage		2.00%		2.00%
Sales discount term				30 days
Trade receivables, credit period				30 days
Number of tranches for private placement transaction \| Tranche								2
Accounts receivable written off		$ 0		$ 0
Other long-term assets		$ 682,000		$ 682,000		$ 174,000
Warrants outstanding \| shares		0		0
Gain (loss) on change in fair value of derivative liabilities		$ 3,610,000	$ (230,000)	$ 8,170,000	$ (366,000)
Number of operating segments \| Segment				1
BioPharma Debt
Significant Accounting Policies [Line Items]
Maximum repayment of future revenue and receivables		128,800,000		$ 128,800,000									$ 150,000,000
Fair value of embedded derivative liability													$ 14,600,000
Gain (loss) on change in fair value of derivative liabilities				5,500,000	(300,000)
Preferred Stock Purchase Option
Significant Accounting Policies [Line Items]
Gain (loss) on change in fair value of derivative liabilities					(946,000)
Derivative liability at fair value									$ 900,000
Embedded Derivative Financial Instruments
Significant Accounting Policies [Line Items]
Gain (loss) on change in fair value of derivative liabilities				8,170,000	$ 470,000
Embedded Derivative Financial Instruments \| BioPharma Debt
Significant Accounting Policies [Line Items]
Maximum repayment of future revenue and receivables												$ 150,000,000
Fair value of embedded derivative liability		0		0		5,500,000
Gain (loss) on change in fair value of derivative liabilities				$ 5,500,000
Top Three Customers \| Gross Product Sales \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage				95.00%	95.00%
Top Three Customers \| Accounts Receivable \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk percentage				95.00%	95.00%
Convertible Debt \| 2014 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount											$ 27,900,000
Fair value of embedded derivative liability						2,100,000
Gain (loss) on change in fair value of derivative liabilities				$ 2,100,000	$ 800,000
Derivative liability at fair value											$ 3,500,000
Convertible Debt \| 2015 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount							$ 3,800,000
Fair value of embedded derivative liability						$ 600,000
Gain (loss) on change in fair value of derivative liabilities				600,000
Derivative liability at fair value							$ 500,000
Convertible Debt \| 2014 Notes and 2015 Notes
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, dividend yield						25.60%
Derivative liability fair value assumptions, risk-free rate						2.90%
Derivative liability fair value assumptions, volatility rate						89.00%
Convertible Debt \| 2012 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount		$ 0		$ 0		$ 0
Note, expected term	24 months
Non Cash \| Convertible Debt \| 2014 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount						24,100,000
Non Cash \| Convertible Debt \| 2015 Notes
Significant Accounting Policies [Line Items]
Convertible senior notes, discount						$ 4,200,000
Warrants Issued October 2009
Significant Accounting Policies [Line Items]
Warrants outstanding \| shares		0		0		0				8,087,388
Warrants exercised \| shares					1,844,585
Warrants expired \| shares					6,242,803
Accounting Standards Update 2015-03 \| Convertible Debt \| 2014 Notes
Significant Accounting Policies [Line Items]
Other long-term assets						$ (1,800,000)
Accounting Standards Update 2015-03 \| Convertible Debt \| 2015 Notes
Significant Accounting Policies [Line Items]
Other long-term assets						(100,000)
Accounting Standards Update 2015-03 \| Scenario, Adjustment
Significant Accounting Policies [Line Items]
Other long-term assets						(1,900,000)
Unamortized debt issuance cost						$ 1,900,000
ASU No. 2016-09
Significant Accounting Policies [Line Items]
Excess tax provision on stock-based awards		$ 300,000		$ 400,000
Deferred tax assets		$ 1,600,000		$ 1,600,000
ASU No. 2016-09 \| Scenario, Previously Reported
Significant Accounting Policies [Line Items]
Excess tax provision on stock-based awards					$ (700,000)
ASU No. 2016-09 \| Restatement Adjustment
Significant Accounting Policies [Line Items]
Excess tax provision on stock-based awards					$ 700,000
Minimum \| Embedded Derivative Financial Instruments \| BioPharma Debt
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term				1 year 3 months 18 days		2 years
Derivative liability fair value assumption, coupon rate				6.60%		6.60%
Derivative liability fair value assumptions, market yields				9.30%		13.00%
Maximum \| Embedded Derivative Financial Instruments \| BioPharma Debt
Significant Accounting Policies [Line Items]
Derivative liability fair value assumptions, term				5 years 7 months 6 days		7 years 3 months 18 days
Derivative liability fair value assumption, coupon rate				12.50%		12.50%
Derivative liability fair value assumptions, market yields				30.70%		30.70%